1. Field of the Invention
The present invention relates to an image information processing apparatus for transferring, e.g., color image information between different types of processing means and processing the information.
2. Description of the Related Art
Recently, an image information processing apparatus such as an electronic filing apparatus has been put into practical use. In this apparatus, image information such as documents produced in large quantities are read by a two-dimensional scanning unit (scanner) upon optical, two-dimensional scanning, and the read image information is stored in an optical disk. Arbitrary image information stored in the optical disk is retrieved and read out. The readout image information is then output from an output unit, e.g., a CRT display unit or a printer, to be visualized.
Expression schemes for color image information employed by such apparatuses are classified into various types according to storage forms. There are, for example, a plane independent scheme shown in FIG. 1A and a packed pixel scheme shown in FIG. 1B. In the plane independent scheme, R, G, and B components of each pixel constituting image information are respectively stored in storage means 1, 2, and 3 in units of R, G, and B planes as pixel color components, i.e., in units of colors. In the packed pixel scheme, R, G and B planes are sequentially stored in units of pixels. However, in either the plane independent scheme o the packed pixel scheme, image information varies in form, e.g., the data width and number of constituent bits of each pixel and plane to be stored in a storage means.
In the conventional apparatuses, therefore, when image information is to be processed (transferred) between a plurality of processing means, e.g., a scanner, a memory, and a printer, which process image information in different forms, the form of the image information is changed to conform to the form of each means upon arithmetic processing by a general CPU or the like.
For this reason, a long processing time is required to transfer image information between processing means which process image information in different forms, thus inevitably imposing limitations on the types of forms of image information to be processed in one apparatus. Moreover, transfer of image information between arbitrary units which process image information in different forms is inefficient and hence cannot be practically performed.